Tries from Jared Payne and Darren Cave in a first half which Ulster dominated from start to finish, complemented by stubborn defence in the final quarter and pinpoint kicking throughout from Pienaar, saw the hosts triumph although Munster did register three tries of their own - two courtesy of the sheer power of their especially combative pack.

The visitors showed admirable spirit and fight to come back from 20 points down to really put it up to Ulster in the second half, even though they lost Donncha O'Callaghan, Cathal Sheridan and Damien Varley to injury.

A fine inside run from Andrew Trimble after several minutes of probing with the boot gave Ulster their first attacking opportunity, eventually leading to the award of a penalty which Pienaar converted from 35 metres out.

Another high take from Trimble moments later - aided by the returning Chris Henry - set the next Ulster move in motion, and with Munster pulled up for an obstruction on Craig Gilroy as he chased down Paddy Jackson's grubber towards the left corner, Ulster kicked their second penalty to touch.

A strong lineout, quick recycling and a smart dink through from Jackson saw full-back Payne, who had come so close to touching down a bobbling ball six days earlier against Leinster, time his dive to perfection to dot down with both hands.

Pienaar converted to establish a 10-point lead for the province after just six minutes' play.

After a centrally-placed Ian Keatley penalty had veered wide of the posts, a Munster offside just shy of halfway gave Pienaar the chance to test his range, and the Springbok impressed with a majestic kick that comfortably found the target.

Keatley should have clawed three points back on 20 minutes, but failed to apply sufficient curve to his kick from the left flank, and the Munster scorecard remained void.

Quickfire passing from Ulster in their very next move got their forwards to the brink of the Munster 22 until a powerhouse tackle from Paul O'Connell knocked the ball from the hands of Tom Court.

However, the Ulstermen kept their foot firmly on the throttle and captain Robbie Diack threatened twice down the right wing just either side of the 30-minute mark.

Three further chances followed hot on the trail - firstly, a sublime 60-metre surge through the middle from Trimble after picking up a poor Munster clearance promised much until Luke Marshall got crowded out on the left.

Then, John Afoa's right foot just strayed into touch on the opposite flank as he looked to score in the corrner from Pienaar's short ruck pass.

It was the third opportunity which counted though and as has been the case so often this season, the talismanic Payne was once again the architect.

The New Zealander ripped the Munster defence asunder with a diagonal 40-metre surge, then supplied Trimble who cut inside and offloaded to Cave - under a tandem of tackles - for the centre to score in the right corner.

Pienaar converted once more for a 20-0 lead and although hard-working Munster centre Ivan Dineen pulled five points back on the stroke of half-time with a well-engineered try, Ulster's dominance was in no doubt.

Indeed, they could have been running off a further 10 points ahead had they enjoyed a little more good fortune.

The second period was an altogether different affair, as table-topping Munster began to move the ball with greater fluency and apply extreme pressure through their increasingly influential forwards.

However, Keatley's poor form off the kicking tee continued as the half opened, his 42nd-minute penalty from distance rebounding to safety off the left hand upright.

Nevertheless, Munster had now found their feet in the game, and bullish mauling from their forwards was rewarded on 48 minutes with a try touched down by prop Kilcoyne - and converted by Keatley's first successful kick from five attempts.

Tommy O'Donnell was the lineout target and the Munster rolling maul was stopped once by the Ulster pack, but they reorganised and forced their way over the line with Kilcoyne grounding the ball.

It was a confidence-boosting try, particularly for replacement hooker Duncan Casey who proved to be a more than able deputy for Varley.

The Shannon clubman's lineout throwing was a key component of Munster's second half revival, as was the supply of quality ball provided by Sheridan's replacement Duncan Williams.

With Munster penalised for popping up at the scrum seven minutes later, Pienaar suffered his first misfire of the night from wide on the right, but strong ball-carrying from the in-form Cave got Ulster right back into the danger zone on the hour mark.

Munster got off somewhat lightly with the concession of only three points at the end of the attack, as Pienaar slotted home a simple penalty from the 22.

The Munster forwards flexed their muscles again on 65 minutes, displaying just how much of a weapon their lineout maul can be.

Number 8 James Coughlan grabbed the try after more powerful mauling from a lineout on the right inside the Ulster 22.

Skipper Peter O'Mahony was found by Casey and the hooker controlled the maul brilliantly with O'Connell before slipping the ball to Coughlan who plunged over from close range. Keatley converted again to bring his side within four points - 23-19.

Pienaar steadied the hosts with a 71st minute penalty after a Munster hand in the ruck - a harsh call - and Rob Penney's charges were unable to respond.

They did go agonisingly close to claiming a bonus point score when another lineout drive saw them cross the Ulster whitewash.

Yet, referee Alain Rolland ruled that the ball had been held up - electing not to use television match official Brian MacNeice - and Ulster breathed a collective sigh of relief.

The excitement of this absorbing interpro tie endured until the last minute, with O'Connell sin-binned for infringing at the ruck and Pienaar slotting home his fifth penalty to secure an important home win - thereby depriving Munster of what would have been a hard-fought and valuable losing bonus point.

The result has moved Ulster back up to third place in the RaboDirect PRO12 standings, six points behind table-topping Munster and two short of the second-placed Ospreys.